Post driving apparatus

ABSTRACT

Apparatus for driving a post into the earth, including a mounting frame assembly for attaching the apparatus to a supporting vehicle, and a vertically extending mast assembly pivotally mounted on the mounting frame assembly for pivotation about horizontal and vertical pivotal axes. A driving assembly is slidably mounted on the mast assembly for vertical reciprocating movement, and a hydraulic piston and cylinder assembly is mounted on the mast assembly and includes a hydraulic cylinder having one end pivotally connected to the lower end of the mast assembly, and a piston rod extending from the upper end of the hydraulic cylinder, and detachably engaging teeth on said driving assembly. The piston rod carries cam rollers at its upper end which engage track plates and camways for automatic disengagement of the piston rod from the teeth on the driving assembly at the stroke limit of the piston rod.

United States Patent 1191 Kopaska Jan. 8, 1974 POST DRIVING APPARATUS [76] Inventor: Arnold F. Kopaska, Guthrie Center, [57] ABSTRACT Iowa 501 15 Apparatus for driving a post into the earth, including a [22] Filed: Aug. 5, 1971 mounting frame assembly for attaching the apparatus to a supporting vehicle, and. a vertically extendin [21] Appl' mast assembly pivotally mounted on the mounting frame assembly for pivotation about horizontal and [52] US. Cl 173/23, 173/37, 173/43, vertical pivotal axes. A driving assembly is slidably 173/124, 173/126 mounted on the mast assembly for vertical reciprocat- [51] Int. Cl. E21c 11/02 ing movement, and a hydraulic piston and cylinder as- [58] Field of Search 173/42,,43, 23, 28, sembly is mounted on the mast assembly and includes 173/126, 124; 94/49 a hydraulic cylinder having one end pivotally connected to the lower end of the mast assembly, and a [56] References Cited piston rod extending from the upper end of the hy- UN1TED STATES PATENTS draulic cylinder, and detachably engaging teeth on 3 400 771 9/1968 Dorn 173/43 said driving assembly Pism ca'ries cam 3:447:63 6/1969 Lisenby lers at its upper end wh1ch engage track plates and 3,605,912 9/l971 Fisher n camways for automatic disengagement of the piston 3,566,977 3 1971 wandell l73/126X r d f the teeth on the d i g ly at the Primary Examiner-Ernest R. Purser Att0rneyDunlap et a1.

stroke limit of the piston rod.

15 Claims, 7 Drawing Figures POST DRIVING APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to power devices for driving a post into the earth, and particularly, post driving apparatus of the type used in conjunction with agricultural tractors or the like for driving fence posts into the earth.

2. Brief Description of the Prior Art Various hydraulically powered fencing aids have been provided in recent years to assist farmers in the essential farming operation of providing adequate fences for the retention of stock, or for the exclusion of stock from crops. One of the most well known types of powered equipment in use is the post hole digger designed for attachment to agricultural tractors, and powered by the power takeoff system of the tractor.

More recently, post hole driving devices have been constructed which may be attached to the front or to the rear of the agricultural tractor (but rarely to either according to choice). These devices receive hydraulic power fluid from a source located on the tractor, and operate to drive, by means of a heavy driver element, the post into the earth.

Although, when conditions for driving posts with an apparatus of the type described are optimum, the devices work well, and a considerable number of posts may be driven in soils of varying hardness in a relatively short period of time, difficulties are frequently encountered where the terrain upon which the posts are to be located is not flat, but is rolling or hilly, and the tractor upon which the post driving apparatus is mounted therefore cannot be parked on level ground druing the driving of the posts. Difficulty encountered in such case arises from the inability of the post driving apparatus to be oriented at selected angles relative to the tractor so that the posts can be driven vertically into the ground. Moreover, in some instances, such as in tight fence corners, where there is little maneuvering room, difficulties of access are encountered, and the post driving apparatus is of little usefulness.

There have also been some types of post driving apparatus which require an operator of the apparatus to stand immediately adjacent a reciprocating driving head or driver assembly with the result that some risk and danger to personal safety is attendant upon the operation of the device in the manner required.

BRIEF DESCRIPTION OF THE PRESENT INVENTION The present invention provides an improved apparatus for driving posts such as fence posts or the like into the earth. The apparatus is operated by a power fluid delivered from a tractor or other suitable vehicle upon which the apparatus may be detachably mounted.

Broadly described, the post driving apparatus of the invention includes a mounting frame assembly which is adjustable in its dimensions and mounting capability to facilitate the detachable engagement of this frame assembly with tractors of varying sizes. The mounting frame assembly is connected to, and supports, a vertically extending mast assembly, with the mast assembly being pivotally mounted on the mounting frame assembly so that the mast assembly may pivot about horizontal and vertical pivotal axes. Access to posts placed in various orientations with respect to the vertical, and atv various angles with respect to the tractor upon which the post driving apparatus is mounted, is thus facilitated. A driving assembly is slidably mounted on the mast assembly for vertical reciprocating movement, and a hydraulic piston and cylinder assembly is connected between the mast assembly and the driving assembly and is utilized for elevating the driving assembly to a stroke-commencement position.

The hydraulic piston and cylinder assembly more specifically includes a hydraulic cylinder which has one end pivotally connected to the lower end portion of the mast assembly, and further includes a piston rod which extends from the upper end of the hydraulic cylinder and detachably engages teeth carried by the driving assembly. For the purpose of automatically disengaging the piston rod from these teeth, the piston rod carries cam rollers at its upper end which engage track plates and camways carried on the mast assembly so that the piston rod is automatically disengaged from the teeth on the driving assembly at or near the upper limit of the travel of the piston rod. 7

An important object of the invention is to provide a post driving apparatus which can be quickly and easily mounted on agricultural tractors of various sizes, and can be quickly connected to the hydraulic system of such tractors for hydraulic powering of the apparatus.

A further object of the invention is to provide a post driving apparatus in which the driving assembly which actually contacts and drives the post can be oriented in a number of selected positions relative to the tractor and relative to the ground, and can be positioned varying distances to one side of, or ahead of, the tractor upon which the post driving apparatus is mounted.

A further object of the invention is to provide a post driving apparatus which may be used with greater safety by an operator than those which have been constructed and utilized in the past.

An additional object of the invention is to provide a post driving apparatus in which the reciprocating driving assembly is more reliably and sturdily mounted on a supporting mast than has been characteristic of previous constructions.

Other objects and advantages, in addition to those specifically mentioned, will be discerned as the following detailed description of the invention is read in conjunction with the accompanying drawings which illustrate the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view showing the post digging apparatus of the present invention mounted on the front end of an agricultural tractor shown in phantom. An alternate operating position of the driving apparatus is shown in dashed lines.

FIG. 2 is a front elevation view of the post driving apparatus of the invention as the apparatus appears when viewed from ahead of an agricultural tractor upon which it is mounted. The tractor is shown in phantom, and an alternate operating position of the post driving apparatus is shown in dashed lines.

FIG. 3 is a plan view of the apparatus and front end portion of the tractor depicted in FIG. 1.

FIG. 4 is a sectional view taken along line d-d of FIG. 3.

FIG. 5 is a front elevation view of the mast and driving assembly forming a portion of the post driving apparatus of the present invention.

FIG. 6 is a detail view of certain parts of the post driving apparatus of the invention.

FIG. 7 is a sectional view taken along line 77 of FIG. 5.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION Referring initially to FIG. 1 of the drawings, shown therein is the forward portion of an agricultural tractor 10. The tractor 10 includes a chassis framework 10a upon which the post driving apparatus of the present invention is detachably mounted. The post driving apparatus of the invention is designated generally by reference numeral 12, and includes a mounting frame assembly 14 by which the apparatus is attached to the tractor. The mounting frame assembly 14 includes a U- shaped subframe having angle iron side members 16 and 18 which are adjustably interconnected by a front member 20. The angle iron front member 20 has a web portion 20a at one of its ends which is bolted through a spacer block 22 to the side member 18. It will be perceived that by changing the thickness of the spacer block 22, the distance which separates the side members 16 and 18 may be varied. In securing the U-shaped subframe to a tractor upon which the post driving apparatus is to be mounted, bolts are extended through selected ones of several holes 24 formed through the vertically extending flange of the angle iron side members 16 and 18, or through holes formed in extension lugs 28 secured to the rearward ends of the side members 16 and 18. This arrangement of holesthrough the angle iron side members 16 and 18, and through the extension lugs 28 provided thereon permit the U-shaped subframe to be easily connected to any one of various types of tractors now marketed, and provided with holes in the framework 10a for receiving various sorts of accessories which are detachably bolted to the tractor. Bolts are also extended through holes in the front member 20 into the framework 100 of the tractor. It will be perceived that by selection ofa properly dimensioned spacer block 22 as the U-shaped subframe is made up, this subframe may be adapted in its dimension for securement to tractor frames of varying widths.

It will be noted in referring to FIG. 3 in the drawings that the side members 16 and 18 of the U-shaped subframe of the mounting frame assembly 14 project forwardly from the forward or front member 20, and that each of these side members has secured to its forward end, a cylindrical sleeve or collar. Thus, a sleeve 30 is secured to the froward end of the side member 16 and a sleeve 32 is secured to the forward end of the side member 18. Extended slidably and rotatably through the sleeves 30 and 32 is a hollow, tubular mounting member 34. A pair of lock rings 36 and 38 are positioned around the tubular mounting member 34 at positions outwardly of the sleeves 30 and 32, and each lock ring carries a set screw to permit it to be locked against sliding movement on the tubular mounting member. It will be perceived that the position of the tubular mounting member 34 relative to the U-shaped subframe can be adjusted by loosening the set screws of the lock rings 36 and 38 and sliding the mounting member in the sleeves 30 and 32 transversely with respect to the tractor. As will be subsequently better understood from the following description, this adjustability of the tubular mounting member 34 in the sleeves 30 and 32 facilitates the positioning of the post driving apparatus in a desired offset position with respect to the line of travel of the tractor as particular post setting requirements may require at different times.

Secured to one end of the tubular mounting member 34 is a C-shaped connection bracket 40. This connection bracket 40 is perhaps best illustrated in FIGS. 1, 2 and 6 of the drawings. The C-shaped bracket 40 has welded or otherwise suitably secured to the upper flange thereof, a vertically extending standard 42. In the illustrated embodiment of the invention, the standard 42 is of generally C-shaped cross-sectional configuration and includes a pair of side flanges 42a and 42b, and a web or back flange 42c. A diagonal brace member 44 is extended at an angle downwardly from the upper portion of the web flange 420 to the tubular mounting member 34 and reinforces and lends mechanical strength to the vertically extending standard 42. At its upper end, the web flange 42c extends past the upper ends of the side flanges 42a and 42b and is bent through a right angle into a horizontal plane to form with a horizontal plate 46 (secured to the upper ends of the flanges 42a and 42b) a pair of parallel plates which receive a pivot pin 48.

The C-shaped connection bracket 40 carries between the horizontally extending legs thereof, a pin (not visible) which has journaled therearound, a pivot sleeve 52 (see FIG. 6). The pivot sleeve 52 extends vertically, and has secured to the medial portion thereof a horizontally extending pivot sleeve 54. The horizontally extending pivot sleeve 54 journals a pivot pin (not visible) passed between a pair of lug flanges 56 which project substantially horizontally of one end of a mast supporting framework 60. At its opposite end, the mast supporting framework 60 has a pair of substantially parallel connection flanges 62 and 64 which have a plurality of holes formed therein to receive bolts used to connect the mast supporting framework 60 to a vertically extending mast assembly designated generally by reference numeral 66.

Before describing in detail, the mast subassembly 66, it should be further pointed out that the mast supporting framework 60 has secured thereto adjacent one of the ears 58 through which the mast supporting frame is pivotally connected to the connection bracket 40, a supporting stand sleeve 68. The supporting stand sleeve 68 slidably receives a vertically extending cylindrical rod 70 forming a portion of a supporting stand, and carrying at its lower end a flat plate 72. The vertical position of the flat, horizontally extending plate 72 in relation to the remainder of the post driving apparatus may be adjusted by sliding the bar 70 in the sleeve 68, and setting the position of this. bar at the place desired by means of a set screw 74 extended through the sleeve 68.

The vertically extending mast assembly 66 includes a pair of vertically extending substantially parallel guide members 76 and 78. The guide members 76 and 78 are configured so as to provide substantially V- shaped guiding surfaces 76a and 780, respectively, at the outer sides thereof, and rearwardly extending flanges 76b and 78b, respectively, extending rearwardly from the guide members. It is to the rearwardly extending flanges 76b and 78b, having a series of vertically spaced connection holes therein, that the flanges 62 and 64 on the mast mounting frame 60 are connected. The guide members 76 and 78 are interconnected at their upper and lower ends by a pair of horizontally extending connector bolts 80 and 82. The mast assembly 66 thus constitutes a rigid framework formed by the connector bolts 30 and 82, and the two vertically extending guide members 76 and 78 which they interconnect.

Carried on, and forming a part of, the mast assembly 66 are a pair of spring metal guide tracks 84 and 86. The spring metal guide track plates 84 and 86 are secured at their upper ends to'V-shaped spacer plates 88 (see FIG. 7) which are, in turn, pivotally connected to the facing inner sides of the pair of vertically extending, substantially parallel guide members 76 and 78 by means of suitable pivot pins or bolts 90. It will be noted from FIG. 7 that the lower end portions of the track plates 84 and 86 are bowed rearwardly from the mast assembly 66. At the upper ends of the guide track plates 84 and 86, and secured to one edge of the V- shaped spacer plates 88, are a pair of camway plates 92 and 94 which extend rearwardly at an acute angle with respect to the vertical for a purpose hereinafter described.

Mounted on the mast assembly 66 is a hydraulic piston and cylinder assembly designated generally by reference numeral 98. (See FIG. 4). The hydraulic piston and cylinder assembly 98 includes a hydraulic cylinder 100 which has its lower end connected to the bolt 82 for pivotation about a horizontal axis. The hydraulic cylinder 100 extends upwardly between the guide members 76 and 78 and has its upper end retained therebetween by an encircling spring element 102 which has its opposite ends connected to the rearwardly projecting flanges 76b and 78b of the two guide members 76 and 78, respectively. Contained within the cylinder 100 is a piston (not seen) which is secured to one end of a piston rod 104 which projects from the upper end of the cylinder 100, and has secured to the free upper end thereof, a U-shaped clevis bracket 106. Each leg of the clevis bracket 106 has rotatably mounted thereon, a cam roller 1 08. The cam rollers 108 bear upon the guide track plates 84 and 86 and follow these plates when the piston rod is extended from the cylinder 101}. It will further be noted in referring to FIG. 4 that the clevis bracket 106 has its central or web portion 106a shaped as a flat bar configured to engage the flat side of a tooth carried by a post driving subassembly as hereinafter described in greater detail.

FIGS. 3, 4 and 5 best illustrate the constructional details of the post driving assembly designated generally by reference numeral 110. In general, the post driving assembly 110 includes a pair of vertically extending, substantially parallel weight boxes 112 and 114. The weight boxes are horizontally spaced from each other, and in the illustrated embodiment, are interconnected by a back plate 116 and a thick driver plate 118 which extends across and interconnects the upper ends of the weight boxes 112 and 114'; In the illustrated embodiment, the weight boxes 112 and 1 14 are of right parallelepiped configuration and are provided at their upper ends with openings closed by removable caps 120 and 122 to facilitate the placement of sand, water or other weighting material in the weight boxes.

It will be noted that each of the weight boxes 112 and 114 has the inside or facing wall thereof (that is, the wall of the respective weight box which faces the other weight box) constructed with a V-shaped indentation or groove formed therein so that each such indentation may receive the complementary V-shaped guiding surface 76a or 78a of one of the vertically extending guide members 76 or 7b. In this way, the post driving assembly is slidably supported on the two guide members 76 and 78 for vertical sliding movement thereon under actuation of the hydraulic piston and cylinder assembly 98 as hereinafter described in greater detail.

Secured to the back plate 116 which interconnects the weight boxes 112 and 114 to each other, and on the opposite side of this back plate from the weight boxes, are a plurality of vertically spaced ratchet teeth 126. Each ratchet tooth 126 has an arcuate or tapered upper side and a flat lower side which lies in a horizontal plane and faces downwardly. The ratchet teeth 126 are aligned with the web portion 1116c of the clevis bracket 106 forming a part of the hydraulic piston and cylinder assembly 98.

For the purpose of directing hydraulic power fluid to the cylinder 100, and for controlling the movements of the cylinder, a four-way control valve 130 is mounted on the side of the mast supporting framework 60 near the forward end thereof. The control valve 130 is constructed so that in one position of its operating lever, hydraulic power fluid directed to the valve via the conduit 132 is permitted to by-pass the hydraulic cylinder 100 and is recirculated directly to the hydraulic power fluid system of the tractor via a conduitwl34. When the valve 130 is shifted to another position, hydraulic fluid entering the valve from the conduit 132 connected at its other end to the hydraulic power fluid supply on the tractor 1b is directed through the valve to a hydraulic power fluid conduit 136 connected to the hydraulic cylinder 10% so as to actuate the piston therein, and extend the piston rod 104 upwardly from the cylinder 100. After the piston rod 164 has been extended to its limit of travel, the control valve 1311 is thrown to a third position which reverses the flow of hydraulic power fluid to the cylinder 100 and permits the piston rod 104 to be retracted into the cylinder.

It will be noted in referring to the location of the control valve 130 that the valve is located to the side, and slightly to the rear, of the post driving assembly 110 so that the position at which an operator of the valve will stand will not subject him to any danger from the moving post driving assembly or structural failure of the post.

Structure is provided in the post driving apparatus of the invention for angling the vertically extending mast assembly 66, and the post driving assembly 110 reciprocably mounted thereon, with respect to the vertical. This permits posts to be driven into the earth at angles if desired, or, in a more frequent application, permits the tractor and the supporting framework for the apparatus to be resting upon sloping ground, while the post driven by the post driving apparatus is driven vertically into the earth. The structure for permitting selective angulation of the vertically extending mast assembly 66 and the post driving assembly 110 includes an adjustable linkage subassembly 140 which, at one end, is con nected between a pair of ears forming a bracket 142 (see FIG. 1) secured to the upper end of the vertically extending standard 42 and facing rearwardly toward the tractor 10. A similar bracket 144 which is welded or otherwise suitably secured to the horizontally extending flange portion of the angle iron side member 18 is connected to the other end of the adjustable linkage subassembly. The opposite ends of the adjustable linkage subassembly 146 are secured in the respective brackets 142 and 144 by means of suitable pivot pins, and the adjustable linkage subassembly includes a tubular sleeve 146 provided with a centrally located, transversely extending turning handle 148. The bores in opposite ends of the sleeve 146 are threaded and receive threaded rods 150 and 152 which have eyes formed at the ends thereof to receive the pivot pins extended through the brackets 142 and 144.

A second structure utilized for adjusting the angular position of the vertically extending mast assembly 66 and post driving assembly 110 with respect to the vertical is a second adjustable linkage subassembly 154. This subassembly includes a U-shaped connector bracket 156 which is pivotally secured by suitable pins to the rearwardly extending flanges 76b and 78b of the vertically extending guide members 76 and 78. The bracket 156 is secured to one end of a bar 158 having its opposite end threaded into one end of a tubular sleeve 160. At its central portion, the tubular sleeve 160 carried a hand wheel 162 to permit it to be rotated about its longitudinal axis, and at its end opposite the end threadedly receiving thebar 158, the sleeve receives another threaded bar 164. The bar 164 has an eye at its end opposite the end threaded into the sleeve 160, and this eye passes around and receives the pivot pin 48.

It will be notedin referring to FIGS. 1 and 2 that the adjustable linkage subassembly 154 can be attached at different vertical levels on the rearwardly extending flanges 76b and 78b of the vertically extending guide members 76 and 78. It will further be apparent that by rotating the hand wheel 162, the overall length of the adjustable linkage subassembly 154 is changed so that the top of the vertically extending mast assembly 66 is pivoted toward or away from the top of the vertically extending standard 42, and its position thereby changed with respect to the vertical.

For the purpose of retaining the mast assembly 66 in a selected position, once it has been moved to such position by pivotation laterally about a vertical axis, a locking linkage 166 is provided. The locking linkage 166 includes an anchor bar 168 secured to the side member 18 of the U-shaped subframe, and an apertured rod 170 pivotally connected to the anchor bar and telescoped into an apertured sleeve 172. The sleeve 172 is pivotally connected to a lug 173 secured to the mast supporting framework 60. A pin 174 is extended through aligned holes in the apertured rod 170 and apertured sleeve 172 to fix the length of locking linkage as needed.

OPERATION In the operation of the post driving apparatus of the invention, the apparatus is first detachably mounted on a self-propelled vehicle, such as the agricultural tractor illustrated in phantom in the drawings. Although the post driving apparatus may, with slight modification, be mounted on the rear of the tractor, it will, in most instances, be preferable to mount the structure on the front of the tractor to facilitate ease of maneuvering the apparatus into a selected position for driving a post.

It may be here pointed out that prior to mounting the post driving apparatus on the forward end of a tractor or other vehicle, the apparatus may be stood upright on the ground through the use of the supporting stand structure which includes the sleeve 68, the cylindrical rod 70 and the flat plate 72. When the rod is extended downwardly to the extent that the flat plate 72 is aligned with the lower end of the post driving assembly 110, three spaced points of support are provided (the two weight boxes 112 and 114 and the flat plate 72) and the post driving apparatus can stand in an upright position ready for mounting on the forward end of the tractor vehicle. It should be further pointed out that in mounting the apparatus on the forward end of the tractor, various sizes and styles of tractor can be employed with the apparatus because of the adjustability of the spacing between the angle iron side members 16 and 18 which is facilitated by the inclusion of the spacer block 22 between these members at one end of the front member 20. Moreover, the provision of the lugs 28 and the plurality of holes 24 in the side members 16 and 18 assure that the mounting frame assembly 14, and more specifically, the Ushaped subframe forming a part thereof, may be accommodated to, and mounted upon, substantially any agricultural tractor.

With the mounting frame assembly 14 mounted on the forward end of the tractor 10 in the manner illustrated in the figures, the weight boxes 112 and 114 are filled with water or sand (or they may have been previously so filled) through the removable caps and 122. The hydraulic connections of the conduits 132, 134, 136 and 138 are made at this time to permit hydraulic power fluid to be delivered to the hydraulic cylinder 100 via the control valve during operation of the post driving apparatus.

After the mounting frame assembly 14 has been secured to the forward end of the tractor 10 in the manner described, the tractor is then driven to the location where the setting and driving of fence posts is to be carried out in maintaining an old, or establishing a new, fence line. This location may be upon terrain such that the tractor 10 cannot be maintained at a level status during the driving of the post, but it will nevertheless be desirable to drive the post vertically into the earth. In a situation of this type, the angulation of the longitudinal axis of the vertically extending mast assembly 66 and the post driving assembly 110 with respect to the vertical and with respect to the plane upon which the four wheels of the tractor rest can be varied by manipulation of the hand wheel 162 and turning handle 148 of the two adjustable linkage subassemblies 154 and 140, respectively. When the vertically extending mast assembly 66 and the post driving assembly 110 are located directly ahead of the tractor 10 or substantially in fore and aft alignment with the vertically extending standard 42, extension or reduction in length of the adjustable linkage subassemblies 140 and 154 will have the effect of canting or angling the mast assembly 66 and post driving assembly 1 10 with respect to the vertical, and with respect to a plane extending transversely to the path of travel of the tractor. In this connection, it may be observed that when the turning handle 148 is rotated so as to increase the overall length of the adjustable linkage subassembly 140, the effect is to cause the upper end .of the vertically extending standard 42 4 to pivot away from the tractor 10. This the vertically extending standard 42 is able to do by reason of its connection to the C-shaped connection bracket 40 which in turn is connected rigidly to one end of the hollow tubular mounting member 34. The hollow tubular mounting member 34 is rotatably mounted in the sleeves 30 and 32 forming a part of the mounting frame assembly 14, so that the mounting member 34 en rotate about its longitudinal axis.

When the adjustable linkage subassembly 154 is extended in length, the effect is, of course, to move the top of the mast assembly 66 and the post driving assembly 110 further from the top of the vertically extending standard 42, and thus to change the angulation of the mast assembly and post driving assembly with respect to the longitudinal axis of the standard. This type of pivotation by the mast assembly 66 and post driving assembly 110 is accommodated by the pivot pin connection of the mast supporting framework 60 through the lug flanges 56 carried on the mast supporting framework 60 with the pivot pin extending through the pivot sleeve 54.

It will be observed that the construction of the post driving apparatus is such that the mast supporting framework 66, as it is interconnected between the mast assembly 66 and the C-shaped connection bracket 40, permits the mast assembly 66, and the post driving as sembly 110 reciprocably mounted thereon, to be swung laterally or to one side with respect to the path of travel of the tractor l0. This amounts to pivotation of framework 60 about a vertical axis substantially coinciding with the longitudinal axis of the vertically extending standard 42. FIG. 2 shows the mast assembly 66 and the post driving assembly 110 as they appear when they have been swung to one side so that the mast supporting framework 60 extends substantially normal with respect to the fore-and-aft axis of the tractor or, stated differently, with respect to the path of travel of the tractor. This adjustability in the post driving apparatus will permit the post driving assembly 114) to be brought over a site at which it is desired to set the post which might not otherwise be accessible were this lateral swivelling movement of the mast assembly 66 not possible.

It should further be pointed out that when the mast assembly 66 and post driving assembly 110 are swung to one side in the manner described, so that they occupy the position in relation to the tractor shown in FIG. 2, angulation of the mast assembly 66 and post driving assembly 110 in two different planes then becomes possible. Thus, when the adjustable linkage subassembly 146 is manipulated to extend or retract its components to lengthen or shorten it, the vertically extending standard 42 is pivoted about the longitudinal axis of the hollow tubular mounting member 34 to lean the mast assembly 66 and post driving assembly 110 forwardly or rearwardly in the sense of the direction of travel of the tractor. There then may also be effected, a sidewise or, stated differently, outwardly or inwardly leaning characteristic in the mast assembly 66 and post driving assembly 116 by lengthening or shortening the adjustable linkage subassembly 154. Of course, various angular components of the directional lean of the mast assembly 66 can be obtained by a combination of manipulations of the two adjustable linkage subassemblies 140 and 154 when the mast assembly 66 is swung to one side in the manner described.

Before departing from a discussion of the utilization of the post driving apparatus in the laterally projecting position shown in FIG. 2, it should be further pointed out that some further extension of the mast assembly 66 and post driving assembly 110 in this direction (that is, further spaced laterally or to one side of th tractor 10) can be obtained by loosening the set screws extended through the lock rings 256 and 36 so that these rings may slide along the hollow tubular mounting member 34. This then permits the hollow tubular mounting member 34 to slide longitudinally in the sleeves 36 and 32 so that the entire post driving apparatus, with the exception of the mounting frame assembly 14, is displaced laterally toward that side of the tractor 10 upon which the mast assembly 66 and post driving assembly are located as shown in FIG. 2 of the drawings.

When the mast assembly 66 and post driving assembly 114) carried thereon have been brought directly over the spot where it is desired to drive a fence post into the earth, the post is set against the back plate 116 of the post driving assembly H6 and between the weight boxes 112 and HM thereof. In many intances,

the post will, at this time, extend upwardly past the driver plate 1 118 which interconnects the upper ends of A the weight boxes H2 and 114. The control valve is then shifted to a position such that hydraulic fluid is delivered via the conduit 136 to the lower end of the hydraulic cylinder Hill This causes the piston rod 104 to be extended, and as it moves upwardly, the web portion of the clevis bracket 166 engages the flat, downwardly facing side of one of the ratchet teeth 126. The engagement is such that the clevis bracket 106 is held in this position against theratchet tooth 126 as the piston rod 104 continues to be extended from the cylinder 104. This causes the cam rollers 16% to press the guide track plates 84 and 36 to a flattened position (see FIG. 7).

As the piston rod 104 continues to be extended, the post driving assembly 116 is caused to slide upwardly on the vertically extending mast assembly 66 as the clevis bracket 106 pushes against the ratchet tooth with which it is in contact. The upward stroke of the piston rod MM will be continued until the rollers 108 reach the camway plates 92 and 94. At this point, the camway plates 92 and 94 commence to wedge the cam rollers W3 and the clevis bracket 1106 which carries these rollers outwardly away from the back plate 1 16 of the post driving assembly 116. Eventually this results in the disengagement of the web portion of the clevis bracket 14116 from the respective ratchet tooth H26 and allows the post driving assembly 110 to fall freely downwardly. Prior to this time, the post has been placed directly under the driver plate 118 of the post driving assembly 110 so that the top of the post is struck by this plate as the post driving assembly 116 descends. A very substantial force is delivered to the top of the post at this time due to the heavy weight constituted by the filled weight boxes M2 and 1M with the result that the post is driven into the earth a distance which will, of course, depend upon the hardness of the earth, the diametric size of the post and the total weight and distance of fall of the post driving assembly 116.

After disengagement of the clevis bracket 1106 from the ratchet tooth 126 carried on the back plate 1116 of the post driving assembly ill), the operator shifts the control valve 130 to retract the piston rod RM and cause the clevis bracket M6 to move downwardly. In its downward movement, the clevis bracket is prevented from becoming engaged by the ratchet teeth 126 by reason of the inclined or tapered upper sides of these teeth. Moreover, a safety feature which is provided in the apparatus is the rearward bow characteristic of the guide track plates 34 and 66. This bow of these spring metal members causes the cam rollers 108 to be displaced rearwardly on the downstroke of the piston rod 104, and this rearward movement is sufficient that, should the falling post driving assembly 110 in some way overtake or not be ahead of the downwardly moving clevis bracket 104, the clevis bracket will nevertheless be displaced rearwardly a sufficient distance to clear the ratchet teeth 126 at this time, and no contact will be established.

The actuation of the control valve 130 to achieve the upward stroke of the piston rod 104 and the entire post driving assembly 110 is then repeated a sufficient number of times to drive the post into the earth to the depth desired. It will, of course, be apparent that some adjustment of the length of the stroke and the position of the post driving assembly 110 relative to the post can be obtained by altering the points of attachment of the mast supporting framework 60 to the rearwardly extending flanges 176b and ll78b of the vertically extending guide members 76 and 78 as may be desired. The bracket 156 secured at one end of the adjustable linkage subassembly 154 can also be adjusted in its position of attachment to the mast assembly.

It will be apparent from the foregoing description of the post driving apparatus of the invention that a versatile, mechanically strong apparatus is provided which can be utilized with substantially any agricultural tractor and which can be used for driving posts into the earth rapidly and safely on almost any type of terrain. The apparatus can be varied in a number of ways in its position in relation to the vehicle upon which it is mounted, and in its attitude with respect to the surface of the ground.

Although a preferred embodiment of the invention has been shown herein, it is to be understood that various changes and modifications to the described structure can be effected without departure from the basic principles of the invention. Changes and modifications of this type which do not entail a relinquishment of these principles are therefore deemed to be circumscribed by the spirit and scope of the invention, except as the same may be necessarily-limited by the appended claims or reasonable equivalents thereof.

What is claimed is:

l. A post driving apparatus comprising:

a mounting frame assembly for detachably mounting the apparatus on a shelf-propelled vehicle, said mounting frame comprising:

an adjustable, U-shaped sub-frame adapted for attachment to variously sized self-propelled vehicles;

a pair of substantially horizontally aligned sleeves mounted on said U-shaped frame; and

an elongated mounting member extended slidably through said sleeves for free rotation about its longitudinal axis;

a vertically extending mast assembly pivotally connected to said mounting member for pivotation on said frame assembly about horizontal and vertical axes; and

a post driving assembly slidably and reciprocably mounted on said mast assembly for driving a post into the earth.

2. A post driving apparatus as defined in claim ll and further characterized as including:

bracket means mounted on one end of said elongated mounting member; and

a mast supporting framework having a first end pivot ally connected to said bracket means for pivotation about horizontal and vertical axes, and having a second end connected to said mast assembly.

3. A post driving apparatus as defined in claim 1 and further characterized as including:

bracket means secured to one end of said elongated mounting member and connected to said mast assembly for pivotation of the mast assembly about horizontal and vertical axes a vertically extending standard mounted on said bracket means and projecting upwardly therefrom;

a first adjustable linkage subassembly connected between the upper end portion of said standard and one of the legs of said U-shaped subframe; and

a second adjustable linkage subassembly connected between the upper end portion of said standard and said mast assembly.

4. A post driving apparatus comprising:

a mounting frame assembly for detachably mounting the apparatus on a self-propelled vehicle;

a vertically extending mast assembly pivotally mounted on the mounting frame assembly for pivotation about horizontal and vertical axes, said mast assembly comprising:

a pair of substantially parallel, vertically extending guide members, each of said guide members including a vertically extending, substantially V- shaped convex guiding surface, and a rearwardly extending flange; and

means rigidly interconnecting said guide members;

a pair of horizontally spaced, hollow weight boxes, each having a vertically extending, V-shaped groove formed therein slidably receiving one of said V-shaped convex guiding surfaces; and

means interconnecting said weight boxes and defining therewith, a vertically extending post receiving channel having post driving means at the upper end thereof.

5. A post driving apparatus as defined in claim 4 and further characterized as including:

a hydraulic piston and cylinder assembly mounted on said mast assembly and including a piston rod extendable in a vertical direction; and

ratchet means on said post driving assembly engageable with said piston rod only upon extension thereof to elevate said post driving assembly on said mast assembly.

6. A post driving apparatus as defined in claim 5 wherein said mounting frame assembly comprises:

an adjustable, U-shaped subframe adapted for attachment to variously sized self-propelled vehicles;

a pair of substantially horizontally aligned sleeves mounted on said U-shaped subframe; and

an elongated mounting member extended slidably through said sleeves and having said mast assembly pivotally connected thereto.

7. A post driving apparatus as defined in claim 6 and further characterized as including:

bracket means mounted on one end of said elongated mounting member; and

a mast supporting framework having a first end pivotally connected to said bracket means for pivotation about horizontal and vertical axes, and having a second end connected to said rearwardly extending flanges of said guide members.

8, A post driving apparatus as defined in claim 7 and further characterized as including:

a vertically extending standard mounted on said bracket means and projecting upwardly therefrom; and

linkage means interconnecting the upper end of said standard with said guide members and with said subframe.

9. A post driving apparatus as defined in claim 8 wherein said linkage means comprises:

a first adjustable linkagesubassembly connected between the upper end portion of said standard and one of the legs of said U-shaped subframe; and

a second adjustable linkage subassembly connected between the upper end portion of said standard and said mast assembly.

10. Apparatus for driving fence posts into the earth comprising:

a mast assembly including generally vertically extending, convex, V-shaped guiding surfaces;

a post driving assembly slidably and reciprocably mounted on said mast assembly and including elongated, V-shaped grooves receiving said guiding surfaces;

a hydraulic piston and cylinder assembly pivotally connected to said mast assembly and including a piston rod detachably engageable with said post driving assembly for elevating said post driving assembly on said mast assembly only when the piston rod of said piston and cylinder assembly is extended;

guide track plates for automatically disengaging said hydraulic piston and cylinder assembly from said post driving assembly at the full extension of said piston rod; and

means for movably mounting said mast assembly on a vehicle.

11. Apparatus for driving posts comprising:

a post driving assembly including weight boxes and a driver plate defining a vertically extending channel for receiving a post to be driven;

means for mounting said post driving assembly on a supporting vehicle for independent pivotation about two horizontal axes and a vertical axis extending normal to one of said horizontal axes;

means for selectively locking said post driving assembly in a selected position of pivotation about said vertical axis; and

means for hydraulically elevating said post driving assembly to a release position followed by automatic release of said post driving assembly to a free falling status.

12. Apparatus for driving posts comprising:

a post driving assembly including weight boxes and a driver plate defining a vertically extending channel for receiving a post to be driven;

means for mounting said post driving assembly on a supporting vehicle for independent pivotation about two horizontal axes and a vertical axis extending normal to one of said horizontal axes, said lid said U-shaped sub-frame and movable in a direction parallel to said web portion;

a connection bracket mounted on one end of said mounting member;

a mast supporting framework pivotally connected to said connection bracket for selective independent pivotation about a horizontal axis and a vertical axis; and

a mast assembly mounted on said mast supporting framework and slidably supporting said post driving assembly; and

means for selectively locking said post driving assembly in a selected position of pivotation about said vertical axis.

13. Apparatus as defined in claim l2 and further characterized as including supporting stand means mounted on said mast supporting framework for stably supporting, with said weight boxes, said apparatus when demounted from a vehicle and rested on the ground.

M. Apparatus for driving posts comprising:

a post driving assembly including weight boxes and a driver plate defining a vertically extending channel for receiving a post to be driven;

means for mounting said post driving assembly on a supporting vehicle for' independent pivotation about two horizontal axes, and about a vertical axis extending normal to one of said horizontal axes, said means for mounting said post driving assembly on a supporting vehicle including:

sub-frarne configured for securement to the vehicle;

a mounting member supported on the subframe for rotation about a horizontal axis;

a mast supporting framework connected to said mounting member for selective independent pivotation about a horizontal axis and about a vertical axis;

a mast assembly mounted on said mast supporting framework and slidably supporting said post driving assembly;

means for selectively locking said post driving assembly, mast assembly and mast supporting framework in a selected position of pivotation about said vertical axis; and

supporting stand means mounted on said mast supporting framework for stably supporting with said weight boxes as a three-point support, said apparatus when demounted from a vehicle and rested on the ground.

15. A post driving apparatus comprising:

a mounting frame assembly for detachably mounting the apparatus on a self-propelled vehicle;

a vertically extending mast assembly pivotally mounted on the mounting frame assembly for pivotation about horizontal and vertical axes; and

a post driving assembly slidably and reciprocably mounted on said mast assembly for driving a post into the earth, said post driving assembly comprising:

weight means reciprocably mounted on said mast assembly;

a hydraulic piston and cylinder assembly mounted on said mast assembly for pivotation about a horizon tal axis, said hydraulic piston and cylinder assembly including a piston rod extendable in a vertical direction;

ratchet means carried on said weight means and reciprocable therewith, said ratchet means being engageable with said piston rod in one position to which said hydraulic piston and cylinder assembly can be pivoted on said horizontal pivotal axis whereby said weight means is engageable with said piston rod upon extension of said piston rod to elevate said weight means on said mast assembly;

guide track plates extending along the path of travel cylinder of said piston and cylinder assembly. 

1. A post driving apparatus comprising: a mounting frame assembly for detachably mounting the apparatus on a shelf-propelled vehicle, said mounting frame comprising: an adjustable, U-shaped sub-frame adapted for attachment to variously sized self-propelled vehicles; a pair of substantially horizontally aligned sleeves mounted on said U-shaped frame; and an elongated mounting member extended slidably through said sleeves for free rotation about its longitudinal axis; a vertically extending mast assembly pivotally connected to said mounting member for pivotation on said frame assembly about horizontal and vertical axes; and a post driving assembly slidably and reciprocably mounted on said mast assembly for driving a post into the earth.
 2. A post driving apparatus as defined in claim 1 and further characterized as including: bracket means mounted on one end of said elongated mounting member; and a mast supporting framework having a first end pivotally connected to said bracket means for pivotation about horizontal and vertical axes, and having a second end connected to said mast assembly.
 3. A post driving apparatus as defined in claim 1 and further characterized as including: bracket means secured to one end of said elongated mounting member and connected to said mast assembly for pivotation of the mast assembly about horizontal and vertical axes; a vertically extending standard mounted on said bracket means and projecting upwardly therefrom; a first adjustable linkage subassembly connected between the upper end portion of said standard and one of the legs Of said U-shaped subframe; and a second adjustable linkage subassembly connected between the upper end portion of said standard and said mast assembly.
 4. A post driving apparatus comprising: a mounting frame assembly for detachably mounting the apparatus on a self-propelled vehicle; a vertically extending mast assembly pivotally mounted on the mounting frame assembly for pivotation about horizontal and vertical axes, said mast assembly comprising: a pair of substantially parallel, vertically extending guide members, each of said guide members including a vertically extending, substantially V-shaped convex guiding surface, and a rearwardly extending flange; and means rigidly interconnecting said guide members; a pair of horizontally spaced, hollow weight boxes, each having a vertically extending, V-shaped groove formed therein slidably receiving one of said V-shaped convex guiding surfaces; and means interconnecting said weight boxes and defining therewith, a vertically extending post receiving channel having post driving means at the upper end thereof.
 5. A post driving apparatus as defined in claim 4 and further characterized as including: a hydraulic piston and cylinder assembly mounted on said mast assembly and including a piston rod extendable in a vertical direction; and ratchet means on said post driving assembly engageable with said piston rod only upon extension thereof to elevate said post driving assembly on said mast assembly.
 6. A post driving apparatus as defined in claim 5 wherein said mounting frame assembly comprises: an adjustable, U-shaped subframe adapted for attachment to variously sized self-propelled vehicles; a pair of substantially horizontally aligned sleeves mounted on said U-shaped subframe; and an elongated mounting member extended slidably through said sleeves and having said mast assembly pivotally connected thereto.
 7. A post driving apparatus as defined in claim 6 and further characterized as including: bracket means mounted on one end of said elongated mounting member; and a mast supporting framework having a first end pivotally connected to said bracket means for pivotation about horizontal and vertical axes, and having a second end connected to said rearwardly extending flanges of said guide members.
 8. A post driving apparatus as defined in claim 7 and further characterized as including: a vertically extending standard mounted on said bracket means and projecting upwardly therefrom; and linkage means interconnecting the upper end of said standard with said guide members and with said subframe.
 9. A post driving apparatus as defined in claim 8 wherein said linkage means comprises: a first adjustable linkage subassembly connected between the upper end portion of said standard and one of the legs of said U-shaped subframe; and a second adjustable linkage subassembly connected between the upper end portion of said standard and said mast assembly.
 10. Apparatus for driving fence posts into the earth comprising: a mast assembly including generally vertically extending, convex, V-shaped guiding surfaces; a post driving assembly slidably and reciprocably mounted on said mast assembly and including elongated, V-shaped grooves receiving said guiding surfaces; a hydraulic piston and cylinder assembly pivotally connected to said mast assembly and including a piston rod detachably engageable with said post driving assembly for elevating said post driving assembly on said mast assembly only when the piston rod of said piston and cylinder assembly is extended; guide track plates for automatically disengaging said hydraulic piston and cylinder assembly from said post driving assembly at the full extension of said piston rod; and means for movably mounting said mast assembly on a vehicle.
 11. Apparatus for driving posts comprising: a post driving assembly including weight boxes and a driver plate defining a vertically extending channel for receiving a post to be driven; means for mounting said post driving assembly on a supporting vehicle for independent pivotation about two horizontal axes and a vertical axis extending normal to one of said horizontal axes; means for selectively locking said post driving assembly in a selected position of pivotation about said vertical axis; and means for hydraulically elevating said post driving assembly to a release position followed by automatic release of said post driving assembly to a free falling status.
 12. Apparatus for driving posts comprising: a post driving assembly including weight boxes and a driver plate defining a vertically extending channel for receiving a post to be driven; means for mounting said post driving assembly on a supporting vehicle for independent pivotation about two horizontal axes and a vertical axis extending normal to one of said horizontal axes, said mounting means comprising: a U-shaped sub-frame; an elongated tubular mounting member rotatably supported on said sub-frame for rotation about the longitudinal axis of said mounting member and extending substantially parallel to the web portion of said U-shaped sub-frame and movable in a direction parallel to said web portion; a connection bracket mounted on one end of said mounting member; a mast supporting framework pivotally connected to said connection bracket for selective independent pivotation about a horizontal axis and a vertical axis; and a mast assembly mounted on said mast supporting framework and slidably supporting said post driving assembly; and means for selectively locking said post driving assembly in a selected position of pivotation about said vertical axis.
 13. Apparatus as defined in claim 12 and further characterized as including supporting stand means mounted on said mast supporting framework for stably supporting, with said weight boxes, said apparatus when demounted from a vehicle and rested on the ground.
 14. Apparatus for driving posts comprising: a post driving assembly including weight boxes and a driver plate defining a vertically extending channel for receiving a post to be driven; means for mounting said post driving assembly on a supporting vehicle for independent pivotation about two horizontal axes, and about a vertical axis extending normal to one of said horizontal axes, said means for mounting said post driving assembly on a supporting vehicle including: a sub-frame configured for securement to the vehicle; a mounting member supported on the subframe for rotation about a horizontal axis; a mast supporting framework connected to said mounting member for selective independent pivotation about a horizontal axis and about a vertical axis; a mast assembly mounted on said mast supporting framework and slidably supporting said post driving assembly; means for selectively locking said post driving assembly, mast assembly and mast supporting framework in a selected position of pivotation about said vertical axis; and supporting stand means mounted on said mast supporting framework for stably supporting with said weight boxes as a three-point support, said apparatus when demounted from a vehicle and rested on the ground.
 15. A post driving apparatus comprising: a mounting frame assembly for detachably mounting the apparatus on a self-propelled vehicle; a vertically extending mast assembly pivotally mounted on the mounting frame assembly for pivotation about horizontal and vertical axes; and a post driving assembly slidably and reciprocably mounted on said mast assembly for driving a post into the earth, said post driving assembly comprising: weight means reciprocably mounted on said mast assembly; a hydraulic piston and cylinder assembly mounted on said mast assembly for pivotation about a horizontal axis, said hydraulic piston and cylinder assembly including a piston rod extendable in a verticaL direction; ratchet means carried on said weight means and reciprocable therewith, said ratchet means being engageable with said piston rod in one position to which said hydraulic piston and cylinder assembly can be pivoted on said horizontal pivotal axis whereby said weight means is engageable with said piston rod upon extension of said piston rod to elevate said weight means on said mast assembly; guide track plates extending along the path of travel of said piston rod; and cam rollers carried by said piston rod and tracking on said guide track means for causing said piston and cylinder assembly to pivot about said horizontal axis and thereby disengage said piston rod from said weight means at a time when said piston rod approaches a position of full extension from the cylinder of said piston and cylinder assembly. 